Automatic dishwashing machine

ABSTRACT

An automatic dishwashing machine comprises a washing chamber ( 3 ) housing a basket ( 4 ) for supporting one or more dishes to be washed, the basket ( 4 ) being rotatable about a predetermined rotation axis (R), motor means ( 5 ) associated with the basket ( 4 ) to drive it into rotation around the rotation axis (R), supply means ( 6 ) of one or more steam jets in said washing chamber ( 3 ). The motor means ( 5 ) are adapted to transmit to said basket ( 4 ) an oscillating motion with predetermined oscillation amplitude (β), said steam jet supply means ( 6 ) comprising one or more nozzles ( 9 ) mutually aligned along a substantially axial direction and adapted to direct respective steam jets along a direction inclined with respect to the vertical.

TECHNICAL FIELD

The present invention is generally applicable to the technical field of household appliances and particularly relates to a machine for the automatic washing of dishes, in particular cups, saucers and cutlery, designed to be used both in the home and in commercial premises.

State of the Art

As known, for washing dishes, both in the home and in offices, bars or commercial premises in general which provide for the dispensing on the spot of drinks and food, the most common alternative to manual dishwashing is constituted from the use of dishwashers provided with a washing chamber sized to contain a relatively large number of dishes.

Inside the washing chamber there is a fixed or removable basket to facilitate the loading of the dishes to be washed and the subsequent extraction of the clean dishes.

Inside the washing chamber there are nozzles for the delivery of water and/or steam jets at settable pressure and temperature values, which intercept the objects placed on the basket.

These solutions, although optimized with regard to the washing cycle, are bulky and unsuitable for allowing the exclusive washing of small dishes, such as cups and coffee cups.

In fact, it is observed that most of the cups and mugs are equipped with a lower base from which a handle, usually annular, protrudes, which stops the fluids reaching the lower base, causing unwanted water stagnation.

In addition, dishwashers currently available on the market are designed to accommodate any type of kitchen utensil, including large items such as pots, lids and serving dishes.

It follows that the washing chamber must have an adequate height to house objects much larger than cups, mugs and glasses.

Therefore, when there are no large items, it is practically impossible to use the entire volume of the washing chamber of a traditional dishwasher, which can be advantageously used only after cooking activities.

Consequently, the structural configuration of the currently available dishwashers affects their use for a limited number of glasses and/or cups and mugs.

From EP2925206, by the same inventor of the present invention, a machine for automatic dishwashing, in particular coffee cups, is known, suitably sized for washing a coffee cup, possibly together with the relative saucer and one or more cutlery small dimensions, such as a coffee spoon, and which allows to solve the problem of stagnation.

This machine comprises a basket suitable for housing the cup and which is rotated by an electric motor so as to perform a predetermined number of complete 360° revolutions.

The cleaning action is exerted by two series of nozzles arranged below the basket and connected to a boiler in order to produce jets of steam that will be directed vertically to sequentially invest both the internal and external surfaces of the cup. A first limitation of this solution is related to the position of the nozzles and to the fact that the basket undergoes complete rotations around its axis.

In fact, it has been observed that in this way, while obtaining a good cleaning of the entire cup, it is not possible to have a substantial sterilization effect on the edge of the cup, which is generally the dirtiest part and to which the greatest attention must be paid, as it is the part designed to come into contact with the lips.

Secondly, the basket is sized for washing a single cup, so that a single washing cycle requires relatively long unit times and relatively high water consumption per unit of crockery and which does not make the machine convenient for domestic use or however for washing a few elements at a time.

Solutions similar to the previous one and which do not solve the aforementioned problems are also described in FR926315, which describes a rotating basket inserted in a frusto-conical washing chamber with an inclined lower wall and nozzles arranged above the rotating drum in such a way as to spray according to a vertical or radial direction with respect to the rotation axis of the drum, and in FR480252, which describes a dishwasher with a fixed drum inserted in a cylindrical chamber and nozzles arranged under the fixed drum.

Scope of the Protection

The object of the present invention is that of overcoming the above drawbacks, realizing a machine for the automatic washing of dishes which is highly efficient and relatively cheap.

A particular object is to provide a machine for the automatic washing of dishes which is particularly optimized for washing small dishes, such as mugs and cups.

Still another object of the present invention is to provide a machine for automatic dishwashing that allows to obtain a thorough disinfection, if not a true sterilization, of the most critical parts of one or more cups, in an optimized way both from the point of view of energy consumption and water consumption.

Still another object of the present invention is to provide a machine for automatic dishwashing which has a relatively high productivity, allowing to treat more than one crockery, and in particular at least two coffee cups, in the same cycle so as to optimize washing times and consumption.

Not least object of the present invention is to provide a machine for automatic dishwashing which has a sufficiently small size to be used also in a domestic environment or in offices, as well as in bars and similar commercial premises.

These purposes, as well as others which will become more apparent hereinafter, are achieved by an automatic dishwashing machine which, in accordance with claim 1, comprises a washing chamber housing a basket for supporting one or more dishes to be washed, said basket being rotatable around a predetermined axis of rotation, motor means associated with said basket to drive it into rotation around said axis of rotation, means for supplying one or more steam jets into said washing chamber.

According to a peculiar features of the invention, the motor means are adapted to transmit to said basket an oscillating motion with a predetermined oscillation amplitude, said steam supplying means comprising one or more nozzles mutually aligned along a substantially axial direction and adapted to direct respective jets of steam along an inclined direction with respect to the vertical.

In this way, the action of the steam jets emitted by the nozzles will be concentrated mainly on the edge of the cup, which must be suitably turned upside down at the start of the cycle, i.e. on the most important part of the cup to be cleaned as it will be the one that will come into contact with the user's lips, being adapted to substantially eliminate any pathogenic germs present and obtaining a sterilizing effect.

The machine will thus allow the dishes to be processed quickly and effectively, obtaining optimal complete cleaning thereof in a relatively short time.

Advantageous embodiments of the machine are obtained in accordance with the dependent claims.

BRIEF DISCLOSURE OF THE DRAWINGS

Further features and advantages of the machine according to the invention will become more apparent in the light of the detailed description of a preferred but not exclusive embodiment of the machine, illustrated by way of non-limiting example with the aid of the accompanying drawing tables wherein:

FIG. 1 is a schematic side view of the machine of the invention without some elements to allow viewing thereinside;

FIG. 2 is a perspective view of the basket according to a preferred embodiment and in which two cups have been loaded;

FIG. 3 is a perspective view of the basket of FIG. 2 in an unloaded condition;

FIG. 4 is a perspective view of the washing chamber containing the basket and in a completely closed condition;

FIG. 5 is a perspective view of the washing chamber containing the basket and in the open door condition;

FIG. 6 is a schematic front view of the basket during use.

Best mode of carrying out the invention With reference to the attached figures, a preferred but not exclusive embodiment of a machine for automatic dishwashing according to the invention is schematically illustrated.

According to this configuration, the machine will be sized to allow two typical coffee cups, of the type commonly used in bars or in the home to serve espresso or mocha type coffee, to be processed at the same time.

However, the machine may be suitably sized to house a different number of cups, even a single cup, or other crockery such as mugs and/or glasses.

As can be seen from FIG. 1, the machine, globally indicated with 1, comprises a containment casing 2 inside which there is a dishwashing chamber 3 and which houses a basket 4 at its inside to support one or more dishes to be washed, in particular two coffee cups C according to the illustrated configuration.

The basket 4 is rotatable around a predetermined axis of rotation R and is connected to the transmission shaft of an electric motor 5 arranged at an axial end of the axis of rotation R, externally to the basket 4, to drive it into rotation around its axis of rotation R.

Means 6 for supplying one or more jets of steam inside the washing chamber 3 are also housed inside the casing 2.

According to the preferred but not exclusive embodiment of the figures, the supplying means 6 comprise a reservoir 7 of clean water, suitably equipped with an anti-limescale filter and pump, not shown, and connected to heating means 8 suitable for transforming the water into steam to be supplied through one or more nozzles 9 located inside the washing chamber 3, inside or outside the basket 4.

The heating means 8 could consist, for example, of a small resistance boiler designed to obtain superheated steam, for example at a minimum temperature of 130° C. if a sterilization effect of the jets is desired.

Inside the casing 2 there will also be a tank 10 for collecting the dirty condensate water which is generated following the cooling of the steam following contact with the dishes and which will be placed in fluid communication with the washing chamber 3 by means of a special exhaust duct 11.

In order to facilitate the drainage of dirty water, the bottom wall of the washing chamber 3 will be suitably inclined towards a drain hole in communication with the exhaust duct 11.

By way of example, the basket 4 may be inclined with an inclination angle α of less than 10°.

Consequently, in the case of a cylindrical washing chamber 3, the basket 4 may also have its axis of rotation R inclined with the same angle α, as in the illustrated configuration.

According to a variant not shown, the washing chamber 3 may have a truncated cone shape and the rotation axis R of the basket 4 may be horizontal.

Conveniently, the electric motor 5 will be of the step-by-step type associated with the basket 4 by means of a mechanical cam, not visible in the figures, and which will be configured to transmit to the basket 4 an oscillating motion with a predetermined oscillation amplitude β around its axis of rotation R.

In turn, the steam supplying means 6 will comprise one or more nozzles 9 mutually aligned along a substantially axial direction and adapted to direct respective jets of steam along a direction inclined with respect to the vertical.

Preferably, the maximum oscillation amplitude β of the basket 4 will be no higher than 60° with respect to a vertical median plane p passing through the rotation axis R.

This value will allow the entire internal and external surface of the cups C to be invested with the jet of steam, focusing particularly on the open edge thereof.

By oscillation amplitude β we mean the amplitude of the oscillation of the basket 4 with respect to the median plane p of the washing chamber 3 passing through the rotation axis R, so that a complete oscillation will have an angle equal to twice the amplitude β with respect to the median plane p.

In particular, the motor means 5 will be configured to impart an oscillation to the basket 4 about its axis of rotation R which is symmetrical with respect to the vertical median plane p.

Preferably, the means 6 for supplying the steam jets will comprise an axial bar provided with a plurality of emission nozzles defined by appropriately calibrated holes to emit respective jets of steam which will not be directed vertically but along an inclined direction.

The outlet holes of each nozzle 9 will have a preferably radial outlet direction and the bar will be arranged on the periphery of the basket 4 in an angularly offset position with respect to the vertical median plane p, with an angular distance not greater than the maximum oscillation amplitude β, so as to ensure that the steam jets mainly hit the open edge of the cups C and the inside of the cups.

According to a preferred configuration, the nozzles 9 are designed to emit respective radial and inclined jets with an angle γ comprised between 40° and 80°, preferably 60°, with respect to the vertical median plane p.

The basket 4 will preferably be sized to house at least two cups C axially side by side.

In this way, with the same cycle it is possible to process at least two cups C in an optimal way, without one of them being an obstacle for sending the steam jet to the other, increasing the productivity of the machine and halving unit consumption of water, as will be clarified later.

In FIGS. 2 to 5 a preferred but not exclusive embodiment of the washing chamber 3 and the relative basket 4 is shown.

In particular, FIG. 2 shows the basket 4 in the loaded condition with two cups C, while FIG. 3 shows the unloaded condition.

It can be observed that the basket 4 comprises a first end carrying crosspiece 12 connected to the electric motor 5 and from which a plurality of axial support rods 13 extend, four in the illustrated configuration, suitably spaced to allow easy entry of the water jets and prevent the dishes from falling.

The rods 13 will then be connected at the other end by a second carrying crosspiece 14 which will facilitate the extraction of the basket 4 from the washing chamber 3.

As can be seen instead from FIGS. 4 and 5, the washing chamber 3 will comprise a cylindrical jacket 15 coaxial to the basket 4 and provided with a closing lid 16 of the chamber 3 through which the basket 4 can be extracted.

Operationally, as can be seen from the schematic sequence of FIG. 6, we will first proceed by inserting the cups C inside the basket 4 with the open edge facing upwards.

At this point, the motor means 5 will be operated to bring the cups C into an inverted position, i.e. with the open edge facing downwards.

From this moment on, the motor 5 will move alternately to impart the oscillating movement to the basket 4 around its axis of rotation R, placing the open edge of the cups C near the nozzles 9.

At the same time the steam supplying means 6 will emit the jets of steam.

At the end of the set cycle time, the motor 5 will interrupt its cycle by keeping the basket 4 in such a position as to always have the cups with the open edge facing downwards, in order to avoid condensation water remaining inside the cups.

As regards the operating parameters, it has been experimentally observed that an optimal work cycle in order to obtain the substantial elimination of pathogenic germs from the edge of the cups C provides for a total tilting time of 24 seconds and a water consumption of 40 cc.

In this way, by processing two cups C at the same time, the unit cycle time will be 12 seconds and the unit water consumption will be 20 cc, making the machine particularly efficient both in terms of energy and water consumption and in terms of process run time, so as to be particularly suitable also for professional uses, for example in bars and similar activities.

The machine described above is susceptible of numerous modifications and variations. All the details can be replaced by other technically equivalent elements, and the materials can be different according to the needs, without departing from the scope of the invention.

Although the machine has been described with particular reference to the attached figures, the reference numbers used in the description and in the claims are used to improve the intelligence of the invention and do not constitute any limitation to the scope of protection claimed. 

1. An automatic dishwashing machine, comprising: a washing chamber (3) housing a basket (4) for supporting one or more dishes to be washed, said basket (4) being rotatable about a predetermined rotation axis (R); motor means (5) associated with said basket (4) to drive it into rotation around said rotation axis (R); supply means (6) of one or more steam jets in said washing chamber (3); characterized in that said motor means (5) are adapted to transmit to said basket (4) an oscillating motion with predetermined oscillation amplitude (β), said steam jet supply means (6) comprising one or more nozzles (9) mutually aligned along a substantially axial direction and adapted to direct respective steam jets along a direction inclined with respect to the vertical.
 2. Machine as claimed in claim 1, characterized in that the maximum oscillation amplitude (β) of said basket is not greater than 60° with respect to a vertical median plane (p) passing through said rotation axis (R).
 3. Machine as claimed in claim 1, characterized in that said steam jet supply means (6) comprise an axial bar provided with a plurality of radial nozzles (9) for the emission of respective steam jets.
 4. Machine as claimed in claim 3, characterized in that said bar is arranged on the periphery of said basket (4) and is angularly offset from said vertical median plane (p) with angular distance not greater than said maximum oscillation amplitude (β).
 5. Machine as claimed in claim 4, characterized in that said nozzles (9) are designed to emit respective inclined jets with an angle (γ) between 40° and 80°, preferably 60°, with respect to said vertical median plane (p).
 6. Machine as claimed in claim 5, characterized in that said nozzles (9) comprise respective hole extending in a radial direction.
 7. Machine as claimed in claim 1, characterized in that said basket (4) is sized to house at least two coffee cups (C) in axially side by side position.
 8. Machine as claimed in any claim 1, characterized in that said rotation axis (R) of said basket (4) is inclined with respect to the horizontal and comprises a first carrying crosspiece (12) connected to said motor means (5) and from which a plurality of axial support rods (13) extends.
 9. Machine as claimed in claim 1, characterized in that said motor means (5) comprise an electric stepper motor provided with a mechanical cam.
 10. Machine as claimed in claim 1, characterized in that said jet steam supply means (6) comprise a clean water reservoir (7) connected to heating means (8) adapted to transform it into steam and to supply said one or more nozzles (9), a tank (10) being also provided for collecting the dirty water in fluid communication with said washing chamber (3). 